subgraph_isomorphisms

All isomorphic mappings between a graph and subgraphs of another graph

All isomorphic mappings between a graph and subgraphs of another graph

Usage

subgraph_isomorphisms(pattern, target, method = c("lad", "vf2"), ...)

Arguments

pattern

The smaller graph, it might be directed or
undirected. Undirected graphs are treated as directed graphs with
mutual edges.

target

The bigger graph, it might be directed or
undirected. Undirected graphs are treated as directed graphs with
mutual edges.

method

The method to use. Possible values: ‘auto’,
‘lad’, ‘vf2’. See their details below.

...

Additional arguments, passed to the various methods.

Value

A list of vertex sequences, corresponding to all
mappings from the first graph to the second.

‘lad’ method

This is the LAD algorithm by Solnon, see the reference below. It has
the following extra arguments:

domains

If not NULL, then it specifies matching
restrictions. It must be a list of target vertex sets, given
as numeric vertex ids or symbolic vertex names. The length of the
list must be vcount(pattern) and for each vertex in
pattern it gives the allowed matching vertices in
target. Defaults to NULL.

induced

Logical scalar, whether to search for an induced
subgraph. It is FALSE by default.

time.limit

The processor time limit for the computation, in
seconds. It defaults to Inf, which means no limit.

‘vf2’ method

This method uses the VF2 algorithm by Cordella, Foggia et al., see
references below. It supports vertex and edge colors and have the
following extra arguments:

vertex.color1, vertex.color2

Optional integer vectors giving the
colors of the vertices for colored graph isomorphism. If they
are not given, but the graph has a “color” vertex attribute,
then it will be used. If you want to ignore these attributes, then
supply NULL for both of these arguments. See also examples
below.

edge.color1, edge.color2

Optional integer vectors giving the
colors of the edges for edge-colored (sub)graph isomorphism. If they
are not given, but the graph has a “color” edge attribute,
then it will be used. If you want to ignore these attributes, then
supply NULL for both of these arguments.